Heater



Jan. 1o, 195o lG. L. JQHNSON ETAL 2,493,970

'HEATER Filed April 4, 1946 l IN VEN TOR s edgfe Z. .fa/fawn By Milian/Yqgffraumer Patented Jan. l0, 1950 HEATER George L. Johnson, New York,N. Y., and William A. Hagerbaumer, Westfield, N. J., assignors toSocony-Vacuum Oil Company, Incorporated, a

corporation of New York Application April 4, 1946, Serial N o 659,442

This invention relates to apparatus for heating a granular solid to anelevated temperature.

The apparatus of this invention is adapted for use in processes forconducting a chemical reaction at high temperature by bringing fluidreactants into direct contact with a highly heated bed of granularsolids. In processes such as the cracking of hydrocarbon fractions toproduce large yields of ethylene at temperatures on the order of 1400 to1600 F. it is highly desirable that the hydrocarbon charge be heatedvery rapidly in order to minimize undesirable secondary reactions. Thisis advantageously accomplished by contact with a hot granular solid andthe apparatus of this invention provides means for heating a granularsolid evenly and efficiently to a suitable high temperature to be laterused for heating the hydrocarbon charge. According to the invention, aflame is directed against and impinges on a surface of the granularsolid to be heated and the hot products of combustion are thereafterpassed directly through a moving bed of granular solid in order to takefull advantage of the heating capacity of the hot gases.

Essentially, the invention contemplates propagation of the flame on thesurface of the granular solid to be heated in order to obtain eflicientcombustion but a portion of the granular solids is shielded from thedirect flame and later used as an economizer section in the region wherethe combustion products are passed directly thro-ugh the mass of solids.

The apparatus of this invention is well adapted to be used in a completesystem utilizing two cycles of solid circulation, in the first of which,reactants are heated to a high temperature by contact with a hot solidand, in the second of which, the reaction products are quenched to atemperature below that at which reaction occurs by direct contact with arelatively cold solid. In thecomplete system described herein, the solidfor quenchingr is cooled by contact with air which is thereafter used aspreheated air for use in the burners of the heater to which theinvention is primarily directed. A heater structure embodying theprinciples of this invention isshown, as a sectional view in sideelevation, in the single figure of the annexed drawing wherein II)represents a shell enclosing the heater. Granular solids to be heatedare supplied through an inlet pipe II at the top of the Vessel to passdownwardly through an upper and a lower heating zone as describedhereinafter.

The upper heating zone is an annular passage defined by an innerlouvered wall I2 and an outer 1 Claim. (Cl. 263-19) louvered wall I3,both depending from a transverse plate I4. The space within the innerlouvered wall I2 constitutes a chamber for supply of hot gases ofcombustion to ow laterally through the annular bed of solids to a spaceabout outer wall I3 from which the ilue gas is discharged by outlet I5.

'Ihe thus heated granular solid passes downwardly and is deflected bymember I6 to a second annular heating zone similarly defined by an outerlouvered wall Il and an inner louvered Wall I8, the space within wall I8 constituting, with the interior of member I6 and the interior of wallI2, a passage for conducting hot gases of combustion from the lower tothe upper heating zone.

It will be seen that the granular solid passing from the upper to thelower heating zone will appear as a circular bed having a face exposedto a combustion chamber defined in part by said bed and in part by arefractory ring I9. Openings for introduction of fuel bumersare providedby nipples 20 spaced around the combustion chamber.

The hot gases of combustion generated within the combustion chamber passdownwardly about the wall Il and thence laterally through the annularbed to the interior of wall I8 from which they pass upwardly to movethrough the bed in the upper heating zone as previously described.

The walls Il and I8 are supported by a plate 2| having a plurality ofgranular solid discharge nipples 22 passing therethrough. The nipples 22are spaced to obtain uniform withdrawal of solids from all parts of theannular bed in the lower heating zone and thereby promote uniform flowthroughout both heating zones. The heated solids collect in the conicalbottom of shell I 0 from which they are withdrawn by pipe 23 for anydesired use.

We claim:

In apparatus for heating a granular solid, a first inner louvered walldening the lower section of a vertical flue, a rst outer louvered walldening an annular vertical heat transfer zone about said lower sectionof said ilue, a second inner louvered wall deiining the upper section ofsaid flue, a second outer louvered wall dening an annular vertical heattransfer zone about said upper section of said flue, means to pass anannular bed of granular solid material downward serially through saidheat transfer zones, means defining a combustion zone open to a surfaceof said bed intermediate said sections of said flue, burners in saidcombustion zone directed against said 'surface to generate a nameimpinging on said surfaee, means to conduct hot products Number ofcombustion from said combustion zone to the 508542 outer tace of saidfirst outer louvered wail, and

means to withdraw gases from about said second 5 outer louvered wall.Number GEORGE L. JOHNSON. 459 95o WILLIAM A. HAGERBAUMER. 5531924REFERENCES man 1 The following references are oi record in the me ofthis patent:

4 e UNITED s'rs'ras PATENTS Name vDate Greer Nov. 14. 1893 FOREIGNPATENTS Country Date Germany 192B Great Britain 1943 Germany 1935

